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  <div class="section" id="module-wave">
<h1>22.5. <tt class="xref docutils literal"><span class="pre">wave</span></tt> &#8212; Read and write WAV files<a class="headerlink" href="#module-wave" title="Permalink to this headline">¶</a></h1>
<p>The <tt class="xref docutils literal"><span class="pre">wave</span></tt> module provides a convenient interface to the WAV sound format.
It does not support compression/decompression, but it does support mono/stereo.</p>
<p>The <tt class="xref docutils literal"><span class="pre">wave</span></tt> module defines the following function and exception:</p>
<dl class="function">
<dt id="wave.open">
<tt class="descclassname">wave.</tt><tt class="descname">open</tt><big>(</big><em>file</em><span class="optional">[</span>, <em>mode</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#wave.open" title="Permalink to this definition">¶</a></dt>
<dd><p>If <em>file</em> is a string, open the file by that name, other treat it as a seekable
file-like object. <em>mode</em> can be any of</p>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">'r'</span></tt>, <tt class="docutils literal"><span class="pre">'rb'</span></tt></dt>
<dd>Read only mode.</dd>
<dt><tt class="docutils literal"><span class="pre">'w'</span></tt>, <tt class="docutils literal"><span class="pre">'wb'</span></tt></dt>
<dd>Write only mode.</dd>
</dl>
<p>Note that it does not allow read/write WAV files.</p>
<p>A <em>mode</em> of <tt class="docutils literal"><span class="pre">'r'</span></tt> or <tt class="docutils literal"><span class="pre">'rb'</span></tt> returns a <tt class="xref docutils literal"><span class="pre">Wave_read</span></tt> object, while a
<em>mode</em> of <tt class="docutils literal"><span class="pre">'w'</span></tt> or <tt class="docutils literal"><span class="pre">'wb'</span></tt> returns a <tt class="xref docutils literal"><span class="pre">Wave_write</span></tt> object.  If <em>mode</em>
is omitted and a file-like  object is passed as <em>file</em>, <tt class="docutils literal"><span class="pre">file.mode</span></tt> is used as
the default value for <em>mode</em> (the <tt class="docutils literal"><span class="pre">'b'</span></tt> flag is still added if  necessary).</p>
</dd></dl>

<dl class="function">
<dt id="wave.openfp">
<tt class="descclassname">wave.</tt><tt class="descname">openfp</tt><big>(</big><em>file</em>, <em>mode</em><big>)</big><a class="headerlink" href="#wave.openfp" title="Permalink to this definition">¶</a></dt>
<dd>A synonym for <a title="open" class="reference external" href="functions.html#open"><tt class="xref docutils literal"><span class="pre">open()</span></tt></a>, maintained for backwards compatibility.</dd></dl>

<dl class="exception">
<dt id="wave.Error">
<em class="property">
exception </em><tt class="descclassname">wave.</tt><tt class="descname">Error</tt><a class="headerlink" href="#wave.Error" title="Permalink to this definition">¶</a></dt>
<dd>An error raised when something is impossible because it violates the WAV
specification or hits an implementation deficiency.</dd></dl>

<div class="section" id="wave-read-objects">
<span id="id1"></span><h2>22.5.1. Wave_read Objects<a class="headerlink" href="#wave-read-objects" title="Permalink to this headline">¶</a></h2>
<p>Wave_read objects, as returned by <a title="open" class="reference external" href="functions.html#open"><tt class="xref docutils literal"><span class="pre">open()</span></tt></a>, have the following methods:</p>
<dl class="method">
<dt id="wave.Wave_read.close">
<tt class="descclassname">Wave_read.</tt><tt class="descname">close</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.close" title="Permalink to this definition">¶</a></dt>
<dd>Close the stream, and make the instance unusable. This is called automatically
on object collection.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getnchannels">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getnchannels</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getnchannels" title="Permalink to this definition">¶</a></dt>
<dd>Returns number of audio channels (<tt class="docutils literal"><span class="pre">1</span></tt> for mono, <tt class="docutils literal"><span class="pre">2</span></tt> for stereo).</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getsampwidth">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getsampwidth</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getsampwidth" title="Permalink to this definition">¶</a></dt>
<dd>Returns sample width in bytes.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getframerate">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getframerate</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getframerate" title="Permalink to this definition">¶</a></dt>
<dd>Returns sampling frequency.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getnframes">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getnframes</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getnframes" title="Permalink to this definition">¶</a></dt>
<dd>Returns number of audio frames.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getcomptype">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getcomptype</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getcomptype" title="Permalink to this definition">¶</a></dt>
<dd>Returns compression type (<tt class="docutils literal"><span class="pre">'NONE'</span></tt> is the only supported type).</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getcompname">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getcompname</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getcompname" title="Permalink to this definition">¶</a></dt>
<dd>Human-readable version of <a title="wave.Wave_read.getcomptype" class="reference internal" href="#wave.Wave_read.getcomptype"><tt class="xref docutils literal"><span class="pre">getcomptype()</span></tt></a>. Usually <tt class="docutils literal"><span class="pre">'not</span> <span class="pre">compressed'</span></tt>
parallels <tt class="docutils literal"><span class="pre">'NONE'</span></tt>.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getparams">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getparams</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getparams" title="Permalink to this definition">¶</a></dt>
<dd>Returns a tuple <tt class="docutils literal"><span class="pre">(nchannels,</span> <span class="pre">sampwidth,</span> <span class="pre">framerate,</span> <span class="pre">nframes,</span> <span class="pre">comptype,</span>
<span class="pre">compname)</span></tt>, equivalent to output of the <tt class="xref docutils literal"><span class="pre">get*()</span></tt> methods.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.readframes">
<tt class="descclassname">Wave_read.</tt><tt class="descname">readframes</tt><big>(</big><em>n</em><big>)</big><a class="headerlink" href="#wave.Wave_read.readframes" title="Permalink to this definition">¶</a></dt>
<dd>Reads and returns at most <em>n</em> frames of audio, as a string of bytes.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.rewind">
<tt class="descclassname">Wave_read.</tt><tt class="descname">rewind</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.rewind" title="Permalink to this definition">¶</a></dt>
<dd>Rewind the file pointer to the beginning of the audio stream.</dd></dl>

<p>The following two methods are defined for compatibility with the <a title="Read and write audio files in AIFF or AIFC format." class="reference external" href="aifc.html#module-aifc"><tt class="xref docutils literal"><span class="pre">aifc</span></tt></a>
module, and don&#8217;t do anything interesting.</p>
<dl class="method">
<dt id="wave.Wave_read.getmarkers">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getmarkers</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.getmarkers" title="Permalink to this definition">¶</a></dt>
<dd>Returns <tt class="xref docutils literal"><span class="pre">None</span></tt>.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.getmark">
<tt class="descclassname">Wave_read.</tt><tt class="descname">getmark</tt><big>(</big><em>id</em><big>)</big><a class="headerlink" href="#wave.Wave_read.getmark" title="Permalink to this definition">¶</a></dt>
<dd>Raise an error.</dd></dl>

<p>The following two methods define a term &#8220;position&#8221; which is compatible between
them, and is otherwise implementation dependent.</p>
<dl class="method">
<dt id="wave.Wave_read.setpos">
<tt class="descclassname">Wave_read.</tt><tt class="descname">setpos</tt><big>(</big><em>pos</em><big>)</big><a class="headerlink" href="#wave.Wave_read.setpos" title="Permalink to this definition">¶</a></dt>
<dd>Set the file pointer to the specified position.</dd></dl>

<dl class="method">
<dt id="wave.Wave_read.tell">
<tt class="descclassname">Wave_read.</tt><tt class="descname">tell</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_read.tell" title="Permalink to this definition">¶</a></dt>
<dd>Return current file pointer position.</dd></dl>

</div>
<div class="section" id="wave-write-objects">
<span id="id2"></span><h2>22.5.2. Wave_write Objects<a class="headerlink" href="#wave-write-objects" title="Permalink to this headline">¶</a></h2>
<p>Wave_write objects, as returned by <a title="open" class="reference external" href="functions.html#open"><tt class="xref docutils literal"><span class="pre">open()</span></tt></a>, have the following methods:</p>
<dl class="method">
<dt id="wave.Wave_write.close">
<tt class="descclassname">Wave_write.</tt><tt class="descname">close</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_write.close" title="Permalink to this definition">¶</a></dt>
<dd>Make sure <em>nframes</em> is correct, and close the file. This method is called upon
deletion.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.setnchannels">
<tt class="descclassname">Wave_write.</tt><tt class="descname">setnchannels</tt><big>(</big><em>n</em><big>)</big><a class="headerlink" href="#wave.Wave_write.setnchannels" title="Permalink to this definition">¶</a></dt>
<dd>Set the number of channels.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.setsampwidth">
<tt class="descclassname">Wave_write.</tt><tt class="descname">setsampwidth</tt><big>(</big><em>n</em><big>)</big><a class="headerlink" href="#wave.Wave_write.setsampwidth" title="Permalink to this definition">¶</a></dt>
<dd>Set the sample width to <em>n</em> bytes.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.setframerate">
<tt class="descclassname">Wave_write.</tt><tt class="descname">setframerate</tt><big>(</big><em>n</em><big>)</big><a class="headerlink" href="#wave.Wave_write.setframerate" title="Permalink to this definition">¶</a></dt>
<dd>Set the frame rate to <em>n</em>.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.setnframes">
<tt class="descclassname">Wave_write.</tt><tt class="descname">setnframes</tt><big>(</big><em>n</em><big>)</big><a class="headerlink" href="#wave.Wave_write.setnframes" title="Permalink to this definition">¶</a></dt>
<dd>Set the number of frames to <em>n</em>. This will be changed later if more frames are
written.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.setcomptype">
<tt class="descclassname">Wave_write.</tt><tt class="descname">setcomptype</tt><big>(</big><em>type</em>, <em>name</em><big>)</big><a class="headerlink" href="#wave.Wave_write.setcomptype" title="Permalink to this definition">¶</a></dt>
<dd>Set the compression type and description. At the moment, only compression type
<tt class="docutils literal"><span class="pre">NONE</span></tt> is supported, meaning no compression.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.setparams">
<tt class="descclassname">Wave_write.</tt><tt class="descname">setparams</tt><big>(</big><em>tuple</em><big>)</big><a class="headerlink" href="#wave.Wave_write.setparams" title="Permalink to this definition">¶</a></dt>
<dd>The <em>tuple</em> should be <tt class="docutils literal"><span class="pre">(nchannels,</span> <span class="pre">sampwidth,</span> <span class="pre">framerate,</span> <span class="pre">nframes,</span> <span class="pre">comptype,</span>
<span class="pre">compname)</span></tt>, with values valid for the <tt class="xref docutils literal"><span class="pre">set*()</span></tt> methods.  Sets all
parameters.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.tell">
<tt class="descclassname">Wave_write.</tt><tt class="descname">tell</tt><big>(</big><big>)</big><a class="headerlink" href="#wave.Wave_write.tell" title="Permalink to this definition">¶</a></dt>
<dd>Return current position in the file, with the same disclaimer for the
<a title="wave.Wave_read.tell" class="reference internal" href="#wave.Wave_read.tell"><tt class="xref docutils literal"><span class="pre">Wave_read.tell()</span></tt></a> and <a title="wave.Wave_read.setpos" class="reference internal" href="#wave.Wave_read.setpos"><tt class="xref docutils literal"><span class="pre">Wave_read.setpos()</span></tt></a> methods.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.writeframesraw">
<tt class="descclassname">Wave_write.</tt><tt class="descname">writeframesraw</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#wave.Wave_write.writeframesraw" title="Permalink to this definition">¶</a></dt>
<dd>Write audio frames, without correcting <em>nframes</em>.</dd></dl>

<dl class="method">
<dt id="wave.Wave_write.writeframes">
<tt class="descclassname">Wave_write.</tt><tt class="descname">writeframes</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#wave.Wave_write.writeframes" title="Permalink to this definition">¶</a></dt>
<dd>Write audio frames and make sure <em>nframes</em> is correct.</dd></dl>

<p>Note that it is invalid to set any parameters after calling <tt class="xref docutils literal"><span class="pre">writeframes()</span></tt>
or <tt class="xref docutils literal"><span class="pre">writeframesraw()</span></tt>, and any attempt to do so will raise
<a title="wave.Error" class="reference internal" href="#wave.Error"><tt class="xref docutils literal"><span class="pre">wave.Error</span></tt></a>.</p>
</div>
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<li><a class="reference external" href="">22.5. <tt class="docutils literal"><span class="pre">wave</span></tt> &#8212; Read and write WAV files</a><ul>
<li><a class="reference external" href="#wave-read-objects">22.5.1. Wave_read Objects</a></li>
<li><a class="reference external" href="#wave-write-objects">22.5.2. Wave_write Objects</a></li>
</ul>
</li>
</ul>

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